Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 131
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Mol Cell ; 80(6): 1123-1134.e4, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33290743

RESUMO

Analyzing the genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from clinical samples is crucial for understanding viral spread and evolution as well as for vaccine development. Existing RNA sequencing methods are demanding on user technique and time and, thus, not ideal for time-sensitive clinical samples; these methods are also not optimized for high performance on viral genomes. We developed a facile, practical, and robust approach for metagenomic and deep viral sequencing from clinical samples. We demonstrate the utility of our approach on pharyngeal, sputum, and stool samples collected from coronavirus disease 2019 (COVID-19) patients, successfully obtaining whole metatranscriptomes and complete high-depth, high-coverage SARS-CoV-2 genomes with high yield and robustness. With a shortened hands-on time from sample to virus-enriched sequencing-ready library, this rapid, versatile, and clinic-friendly approach will facilitate molecular epidemiology studies during current and future outbreaks.


Assuntos
COVID-19/genética , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , RNA Viral/genética , SARS-CoV-2/genética , Sequenciamento Completo do Genoma , Animais , Humanos , Camundongos , Células NIH 3T3 , RNA Viral/metabolismo , SARS-CoV-2/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(2): e2311930121, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38175861

RESUMO

When making contact with an undercooled target, a drop freezes. The colder the target is, the more rapid the freezing is supposed to be. In this research, we explore the impact of droplets on cold granular material. As the undercooling degree increases, the bulk freezing of the droplet is delayed by at least an order of magnitude. The postponement of the overall solidification is accompanied by substantial changes in dynamics, including the spreading-retraction process, satellite drop generation, and cratering in the target. The solidification of the wetted pores in the granular target primarily causes these effects. The freezing process over the pore dimension occurs rapidly enough to match the characteristic timescales of impact dynamics at moderate undercooling degrees. As a result, the hydrophilic impact appears "hydrophobic," and the dimension of the solidified droplet shrinks. A monolayer of cold grains on a surface can reproduce these consequences. Our research presents a potential approach to regulate solidified morphology for subfreezing drop impacts. It additionally sheds light on the impact scenario of strong coupling between the dynamics and solidification.

3.
J Infect Dis ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315770

RESUMO

BACKGROUND: Abnormal cervical cytology is commonly observed in women living with HIV (WLWH). METHODS: A cross-sectional study was conducted with 130 WLWH and 147 age-matched healthy controls, who underwent gynecological examinations at Beijing Ditan Hospital. The presence of abnormal cervical cytology in WLWH was predicted after performing a logistic regression analysis. RESULTS: Multivariate logistic regression revealed three independent factors, among which CD4 cell counts of more than 350 cells/µL was the protective factor, while human papillomavirus infection and abnormal vaginal pH were the risk factors. CONCLUSIONS: Vaginal microecological disorders can increase the risk of abnormal cervical cytology in WLWH.

4.
J Virol ; 97(9): e0060123, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37676001

RESUMO

Canine coronavirus-human pneumonia-2018 (CCoV-HuPn-2018) was recently isolated from a child with pneumonia. This novel human pathogen resulted from cross-species transmission of a canine coronavirus. It has been known that CCoV-HuPn-2018 uses aminopeptidase N (APN) from canines, felines, and porcines, but not humans, as functional receptors for cell entry. The molecular mechanism of cell entry in CCoV-HuPn-2018 remains poorly understood. In this study, we demonstrated that among the nine APN orthologs tested, the APN of the Mexican free-tailed bat could also efficiently support CCoV-HuPn-2018 spike (S) protein-mediated entry, raising the possibility that bats may also be an alternative host epidemiologically important for the transmission of this virus. The glycosylation at residue N747 of canine APN is critical for its receptor activity. The gain of glycosylation at the corresponding residues in human and rabbit APNs converted them to functional receptors for CCoV-HuPn-2018. Interestingly, the CCoV-HuPn-2018 spike protein pseudotyped virus infected multiple human cancer cell lines in a human APN-independent manner, whereas sialic acid appeared to facilitate the entry of the pseudotyped virus into human cancer cells. Moreover, while host cell surface proteases trypsin and TMPRSS2 did not promote the entry of CCoV-HuPn-2018, endosomal proteases cathepsin L and B are required for the entry of CCoV-HuPn-2018 in a pH-dependent manner. IFITMs and LY6E are host restriction factors for the CCoV-HuPn-2018 entry. Our results thus suggest that CCoV-HuPn-2018 has not yet evolved to be an efficient human pathogen. Collectively, this study helps us understand the cell tropism, receptor usage, cross-species transmission, natural reservoir, and pathogenesis of this potential human coronavirus. IMPORTANCE Viral entry is driven by the interaction between the viral spike protein and its specific cellular receptor, which determines cell tropism and host range and is the major constraint to interspecies transmission of coronaviruses. Aminopeptidase N (APN; also called CD13) is a cellular receptor for HCoV-229E, the newly discovered canine coronavirus-human pneumonia-2018 (CCoV-HuPn-2018), and many other animal alphacoronaviruses. We examined the receptor activity of nine APN orthologs and found that CCoV-HuPn-2018 utilizes APN from a broad range of animal species, including bats but not humans, to enter host cells. To our surprise, we found that CCoV-HuPn-2018 spike protein pseudotyped viral particles successfully infected multiple human hepatoma-derived cell lines and a lung cancer cell line, which is independent of the expression of human APN. Our findings thus provide mechanistic insight into the natural hosts and interspecies transmission of CCoV-HuPn-2018-like coronaviruses.


Assuntos
Antígenos CD13 , Infecções por Coronavirus , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus , Animais , Cães , Humanos , Coelhos , Antígenos CD13/metabolismo , Quirópteros/virologia , Coronavirus/fisiologia , Pneumonia , Glicoproteína da Espícula de Coronavírus/metabolismo
5.
Langmuir ; 40(12): 6582-6586, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38477650

RESUMO

We investigate a subfreezing droplet impact scenario in a low-humidity environment, where the target is a cold granular monolayer. When the undercooling degree of targets passes a threshold, such a granular layer effectively postpones the bulk freezing time of the droplet in comparison with the impact on the bare substrate underneath. In this case, the retraction of the droplet after impact reduces the contact area with the cold substrate, even though both the grains and the substrate are wettable to the liquid. We find that the significant changes in the dynamic behavior are triggered by freezing the liquid that wets the pores. Owing to the small dimension of the pores, the freezing process is rapid enough to match the dynamics over the droplet dimension. In certain circumstances, the rapid freezing may even stop liquid penetration and shed icing from the surface underneath.

6.
Environ Sci Technol ; 58(21): 9446-9455, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38748977

RESUMO

Biological pretreatment is a viable method for enhancing biogas production from straw crops, with the improvement in lignocellulose degradation efficiency being a crucial factor in this process. Herein, a metagenomic approach was used to screen core microorganisms (Bacillus subtilis, Acinetobacter johnsonii, Trichoderma viride, and Aspergillus niger) possessing lignocellulose-degrading abilities among samples from three environments: pile retting wheat straw (WS), WS returned to soil, and forest soil. Subsequently, synthetic microbial communities were constructed for fermentation-enzyme production. The crude enzyme solution obtained was used to pretreat WS and was compared with two commercial enzymes. The synthetic microbial community enzyme-producing pretreatment (SMCEP) yielded the highest enzymatic digestion efficacy for WS, yielding cellulose, hemicellulose, and lignin degradation rates of 39.85, 36.99, and 19.21%, respectively. Furthermore, pretreatment of WS with an enzyme solution, followed by anaerobic digestion achieved satisfactory results. SMCEP displayed the highest cumulative biogas production at 801.16 mL/g TS, which was 38.79% higher than that observed for WS, 22.15% higher than that of solid-state commercial enzyme pretreatment and 25.41% higher than that of liquid commercial enzyme pretreatment. These results indicate that enzyme-pretreated WS can significantly enhance biogas production. This study represents a solution to the environmental burden and energy use of crop residues.


Assuntos
Biocombustíveis , Triticum , Triticum/metabolismo , Anaerobiose , Fermentação , Lignina/metabolismo
7.
Plant Dis ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411606

RESUMO

Praxelis clematidea is an invasive herbaceous plant belonging to Asteraceae family. From August to November 2020, the plants showing severe witches'-broom symptoms were found in farms and roadsides from Ding'an of Hainan Province, a tropical island of China. The disease symptoms were suggestive of phytoplasma infection. For pathogen detection, P. clematidea samples consisting of six symptomatic and three asymptomatic plants were collected from the farms and roadsites of Ding'an with 40 % incidence by conducting surveys and statistics. Total nucleic acids were extracted using 0.10 g of fresh leaf tissues of the plant through CTAB DNA extraction method. Conserved gene sequences of 16S rRNA and secA genes from phytoplasma were amplified by direct PCR using primer pairs of R16mF2/R16mR1 and secAfor1/secArev3, respectively. R16mF2/R16mR1 PCR amplicons were obtained for all symptomatic samples but not from the symptomless plants. The amplicons were purified and sequenced by Biotechnology (Shanghai) Co., Ltd. (Guangzhou, China). Sequences of 16S rRNA gene (1323 bp) and secA (732 bp) were obtained and all the gene sequences were identical, designated as PcWB (Praxelis clematidea witches'-broom)-hnda. Representative sequencs were deposited in Genbank with accession numbers of PP098736 (16S rDNA) and PP072216 (secA). Nucleotide BLAST (Basic Local Alignment Search Tool) search based on 16S rRNA gene sequences indicated that PcWB-hnda had 100% sequence identity (1323/1323) with 'Candidatus Phytoplasma asteris'-related strains belonging to 16SrI group like Waltheria indica virescence phytoplasma (MW353909) and Capsicum annuum yellow crinkle phytoplasma (MT760793); had 99.62 % sequence identity (1321/1326) with the phytoplasma strains of 16SrI group such as Oenothera phytoplasma (M30790). RFLP (Restriction Fragment Length Polymorphism) pattern derived from 16Sr RNA gene sequences by iPhyClassifier showed identical (similarity coefficient=1.00) to the reference pattern of 16SrI-B subgroup (GenBank accession number: AP006628). The results obtained demonstrate that the phytoplasma strain PcWB-hnda under study is a member of 16SrI-B subgroup. A BLAST search based on secA gene sequences indicated that PcWB-hnda shares 100% sequence identity (732/732 bp) with Pericampylus glaucus witches'-broom phytoplasma (MT875200), 99% sequence identify (728/732 bp) with onion yellows phytoplasma OY-M(AP006628), and 99% sequence identify (729/732 bp) with rapeseed phyllody phytoplasma isolate RP166 (CP055264), among other phytoplasma strains that belong to 16SrI group. Previous studies demonstrated that P. clematidea can be infected by phytoplasmas affiliate to the 16SrII group (GenBank accession number: KY568717 and EF061924) in Hainan Island of China. To our knowledge, this is the first report of a natural infection of P. clematidea by a group 16SrI phytoplasma in the Island of China. 16SrI group can infect agronomic important species such as areca palm in the island and P. clematidea can be a reservoir of 16SrI phytoplasmas. Therefore, it is necessary to search of potential vectors of the pathogens, which would contribute to epidemiological monitoring and prevention of the related diseases.

8.
J Sci Food Agric ; 104(9): 5021-5030, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38296914

RESUMO

BACKGROUND: Baijiu brewing is a complex and multifaceted multimicrobial co-fermentation process, in which various microorganisms interact to form an interdependent micro-ecosystem, subsequently influencing metabolic activities and compound production. Among these microorganisms, Bacillus, an important bacterial genus in the liquor brewing process, remains unclear in its role in shaping the brewing microbial community and its functional metabolism. RESULTS: A baijiu fermentation system was constructed using B. subtilis JP1 isolated from native jiupei (grain mixture) combined with daqu (a saccharifying agent) and huangshui (a fermentation byproduct). Based on high-throughput amplicon sequencing analysis, it was evident that B. subtilis JP1 significantly influences bacterial microbial diversity and fungal community structure in baijiu fermentation. Of these, Aspergillus and Monascus emerge as the most markedly altered microbial genera in the jiupei community. Based on co-occurrence networks and bidirectional orthogonal partial least squares discriminant analysis models, it was demonstrated that the addition of B. subtilis JP1 intensified microbial interactions in jiupei fermentation, consequently enhancing the production of volatile flavor compounds such as heptanoic acid, butyl hexanoate and 3-methylthiopropanol in jiupei. CONCLUSION: B. subtilis JP1 significantly alters the microbial community structure of jiupei, enhancing aroma formation during fermentation. These findings will contribute to a broader application in solid-state fermentation. © 2024 Society of Chemical Industry.


Assuntos
Bacillus subtilis , Fermentação , Bacillus subtilis/metabolismo , Microbiota , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/química , Metaboloma , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Bebidas Alcoólicas/microbiologia , Bebidas Alcoólicas/análise , Aspergillus/metabolismo , Aspergillus/isolamento & purificação , Aromatizantes/metabolismo , Aromatizantes/química , Fungos/metabolismo , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Monascus/metabolismo , Monascus/genética
9.
Chin Med Sci J ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773789

RESUMO

Vertebral artery dissection is a rare pathology that causes ischemic stroke in young people. Cervical massage, especially improper pulling manipulation, is a cause of vertebral artery dissection. We present a case of 32-year-old woman who developed acute multiple posterior circulation ischemic cerebral infarctions as a result of left vertebral artery V4 segment dissection after receiving neck massage. She underwent emergency vertebral artery stent implantation at the site of the dissection. Symptoms were relieved the day after treatment. The patient recovered without adverse complications or endovascular restenosis in the following year.

10.
J Med Virol ; 95(12): e29258, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38054542

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an acute infectious disease prevalent in East Asia with a high mortality rate (5%-30%). Reverse transcription loop-mediated isothermal amplification (RT-LAMP), a rapid nucleic acid-based diagnostic technique, is a useful alternative for the clinical diagnosis of SFTS, particularly in resource-limited hospitals or rural clinics in SFTS virus-endemic regions. However, the actual clinical sensitivity and specificity of RT-LAMP remain unclear. This study evaluated the field application of RT-LAMP. This prospective field study included 130 patients with laboratory-confirmed SFTS from Yantai, Shandong Province, China. Two sets of RT-LAMP primers were validated, and one set of RT-LAMP assays was optimized for field detection. Nucleic acids of serially collected serum/plasma samples were identified using quantitative reverse transcription polymerase chain reaction (RT-qPCR) and RT-LAMP. In laboratory tests, we optimized the detection time of primer set 2 for the RT-LAMP to 60 min. Notably, the onsite testing of 279 plasma samples from patients with SFTS revealed that the sensitivity and specificity of the test were 81.9% and 96.3%, respectively. We also analyzed samples with different durations of the disease, and our study showed that the sensitivity of RT-LAMP detection at the beginning of admission was 89.92%. Univariate analysis showed that the detection rate of RT-LAMP was similar to that of RT-qPCR in the first 5 days of the disease course and was lower than that of RT-qPCR on Days 6 and 14-15 of the disease course. The positive detection rate in patients aged ≥ 65 years was significantly higher than that in younger age groups. RT-LAMP is a simple, suitable, and rapid clinical detection method of SFTS onsite screening. It is more suitable for screening patients in the early stages of the disease and analyzing samples obtained from patients aged ≥ 65 years before the 6th day of the disease course.


Assuntos
Transcrição Reversa , Febre Grave com Síndrome de Trombocitopenia , Humanos , Febre Grave com Síndrome de Trombocitopenia/diagnóstico , Laboratórios Clínicos , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade , RNA Viral/genética
11.
J Med Virol ; 95(10): e29136, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37804496

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron harbors more than 30 mutations of the spike protein and exhibits substantial immune evasion. Although previous study indicated that BNT162b2 messenger RNA vaccine induces potent cross-clade pan-sarbecovirus neutralizing antibodies in survivors of the infection by SARS-CoV-1, the neutralization activity and Fc-mediated effector functions of these cross-reactive antibodies elicited in SARS-CoV-1 survivors to Omicron subvariants still remain largely unknown. In this study, the neutralization activity and Fc-mediated effector functions of antibodies boosted by a third dose vaccination were characterized in SARS-CoV-1 convalescents and healthy individuals. Potent cross-clade broadly neutralizing antibodies were observed in SARS-CoV-1 survivors who received a three-dose vaccination regimen consisting of two priming doses of CoronaVac followed by one booster dose of the protein subunit vaccine ZF2001. However, the induced antibodies exhibited both reduced neutralization and impaired Fc effector functions targeting multiple Omicron subvariants. Importantly, the data also support the notion that immune imprints resulted from SARS-CoV-1 infection may exacerbate the impairment of neutralization activity and Fc-mediated effector functions to Omicron subvariants and provided invaluable information to vaccination strategy in future.


Assuntos
Vacina BNT162 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Vacinas de Subunidades Antigênicas , SARS-CoV-2 , Sobreviventes , Anticorpos Neutralizantes , Anticorpos Antivirais
12.
Mod Rheumatol ; 33(4): 823-829, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35727178

RESUMO

OBJECTIVES: To determine the frequency of symptoms meeting Rome IV functional bowel disorder (FBD) in patients with ankylosing spondylitis (AS), investigate factors associated with FBD symptoms, and assess whether having FBD symptoms might influence AS disease activity. METHODS: In this cross-sectional study, we enrolled 153 AS patients without known colonic ulcers and 56 sex- and age-matched controls to evaluate FBD (or its subtypes) symptoms. Disease characteristics were also evaluated in the AS group. RESULTS: Sixty (39.2%) of 153 AS patients had FBD symptoms, which were more prevalent than controls (23.2%). Besides, symptoms compatible with irritable bowel syndrome (IBS) and chronic diarrhoea were detected in 18 and 43 AS patients, respectively. For the AS group, multivariable logistic regression analyses showed that symptoms of FBD, IBS, and chronic diarrhoea were negatively associated with using non-steroidal anti-inflammatory drugs and positively associated with comorbid fibromyalgia, respectively. In exploration about the effects of FBD (or its subtypes) symptoms on AS disease activity by multivariable linear regression analyses, FBD symptoms and chronic diarrhoea had universal positive associations with assessments of AS disease characteristics, respectively. CONCLUSIONS: Patients with AS had frequent symptoms compatible with FBD, IBS, and chronic diarrhoea, proportions of which were lower in those with non-steroidal anti-inflammatory drug use. The improvement of FBD symptoms and chronic diarrhoea might be conducive to the disease status of AS patients.


Assuntos
Gastroenteropatias , Síndrome do Intestino Irritável , Espondilite Anquilosante , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/diagnóstico , Estudos Transversais , Cidade de Roma , Espondilite Anquilosante/complicações , Gastroenteropatias/diagnóstico , Diarreia/complicações , Anti-Inflamatórios não Esteroides/uso terapêutico , Inquéritos e Questionários
13.
BMC Cancer ; 22(1): 619, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35668369

RESUMO

BACKGROUND: An imbalance of intracellular iron metabolism can lead to the occurrence of ferroptosis. Ferroptosis can be a factor in the remodeling of the immune microenvironment and can affect the efficacy of cancer immunotherapy. How to combine ferroptosis-promoting modalities with immunotherapy to suppress triple-negative breast cancer (TNBC) has become an issue of great interest in cancer therapy. However, potential biomarkers related to iron metabolism and immune regulation in TNBC remain poorly understand. METHODS: We constructed an optimal prognostic TNBC-IMRGs (iron metabolism and immune-related genes) signature using least absolute shrinkage and selection operator (LASSO) cox regression. Survival analysis and ROC curves were analyzed to identify the predictive value in a training cohort and external validation cohorts. The correlations of gene signature with ferroptosis regulators and immune infiltration are also discussed. Finally, we combined the gene signature with the clinical model to construct a combined model, which was further evaluated using a calibration curve and decision curve analysis (DCA). RESULTS: Compared with the high-risk group, TNBC patients with low-risk scores had a remarkably better prognosis in both the training set and external validation sets. Both the IMRGs signature and combined model had a high predictive capacity, 1/3/5- year AUC: 0.866, 0.869, 0.754, and 1/3/5-yaer AUC: 0.942, 0.934, 0.846, respectively. The calibration curve and DCA also indicate a good predictive performance of the combined model. Gene set enrichment analysis (GSEA) suggests that the high-risk group is mainly enriched in metabolic processes, while the low-risk group is mostly clustered in immune related pathways. Multiple algorithms and single sample GSEA further show that the low-risk score is associated with a high tumor immune infiltration level. Differences in expression of ferroptosis regulators are also observed among different risk groups. CONCLUSIONS: The IMRGs signature based on a combination of iron metabolism and immune factors may contribute to evaluating prognosis, understanding molecular characteristics and selecting treatment options in TNBC.


Assuntos
Ferroptose , Neoplasias de Mama Triplo Negativas , Biomarcadores Tumorais/genética , Ferroptose/genética , Humanos , Ferro , Prognóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Microambiente Tumoral/genética
14.
Immun Ageing ; 19(1): 63, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36514074

RESUMO

BACKGROUND: It has been widely accepted that monocytes are one of the central mediators contributing to inflammaging. However, it remains unclear whether aged monocytes, similar to aged T cells, have characteristics of hyperactivation and increased expression of co-inhibitory molecules. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from young (21-40 years old), middle-aged (41-60 years old), and older human subjects (> 60 years old). Flow cytometry was used to monitor changes in the expression of surface molecules of monocyte subsets and cytokine-producing capacity. RESULTS: We observed increased tumor necrosis factor-α: TNF-α and decreased interleukin-6 (IL-6) production in monocytes from older adults compared with young and middle-aged adults. Older adults had a greater percentage of intermediate and non-classical monocyte subsets, along with increased levels of the immune activation markers human leukocyte antigen-DR (HLA-DR), and adhesion molecules cluster of differentiation molecule 11b (CD11b) and L-selectin (CD62L). Furthermore, we observed increased C-C motif chemokine receptor 2 (CCR2) expression on classical monocytes and decreased C-X3-C motif chemokine receptor 1 (CX3CR1) expression on non-classical monocytes in older adult subjects. The expression of co-inhibitory receptors was reduced on monocyte subsets in older adults. CONCLUSIONS: Circulating monocytes in older adults exhibit increased expression of activation, adhesion, and migration markers, but decreased expression of co-inhibitory molecules.

15.
Clin Infect Dis ; 73(9): e2814-e2817, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33086379

RESUMO

Intrahost analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomic sequences identified 2 viral haplotypes comprised of 3 genetically linked mutations from the respiratory and intestinal tracts of a patient with coronavirus disease 2019. Spatiotemporal data suggest that this patient initially had dual infection of 2 SARS-CoV-2 variants, which subsequently redistributed into the 2 systems.


Assuntos
COVID-19 , SARS-CoV-2 , Genômica , Humanos , Sistema Respiratório
16.
J Virol ; 94(18)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32661139

RESUMO

The COVID-19 pandemic has caused an unprecedented global public health and economic crisis. The origin and emergence of its causal agent, SARS-CoV-2, in the human population remains mysterious, although bat and pangolin were proposed to be the natural reservoirs. Strikingly, unlike the SARS-CoV-2-like coronaviruses (CoVs) identified in bats and pangolins, SARS-CoV-2 harbors a polybasic furin cleavage site in its spike (S) glycoprotein. SARS-CoV-2 uses human angiotensin-converting enzyme 2 (ACE2) as its receptor to infect cells. Receptor recognition by the S protein is the major determinant of host range, tissue tropism, and pathogenesis of coronaviruses. In an effort to search for the potential intermediate or amplifying animal hosts of SARS-CoV-2, we examined receptor activity of ACE2 from 14 mammal species and found that ACE2s from multiple species can support the infectious entry of lentiviral particles pseudotyped with the wild-type or furin cleavage site-deficient S protein of SARS-CoV-2. ACE2 of human/rhesus monkey and rat/mouse exhibited the highest and lowest receptor activities, respectively. Among the remaining species, ACE2s from rabbit and pangolin strongly bound to the S1 subunit of SARS-CoV-2 S protein and efficiently supported the pseudotyped virus infection. These findings have important implications for understanding potential natural reservoirs, zoonotic transmission, human-to-animal transmission, and use of animal models.IMPORTANCE SARS-CoV-2 uses human ACE2 as a primary receptor for host cell entry. Viral entry mediated by the interaction of ACE2 with spike protein largely determines host range and is the major constraint to interspecies transmission. We examined the receptor activity of 14 ACE2 orthologs and found that wild-type and mutant SARS-CoV-2 lacking the furin cleavage site in S protein could utilize ACE2 from a broad range of animal species to enter host cells. These results have important implications in the natural hosts, interspecies transmission, animal models, and molecular basis of receptor binding for SARS-CoV-2.


Assuntos
Doenças dos Animais/metabolismo , Doenças dos Animais/virologia , Betacoronavirus/fisiologia , Infecções por Coronavirus/veterinária , Pandemias/veterinária , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/veterinária , Receptores Virais/metabolismo , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2 , Animais , Betacoronavirus/classificação , COVID-19 , Linhagem Celular , Especificidade de Hospedeiro , Humanos , Modelos Moleculares , Mutação , Peptidil Dipeptidase A/química , Filogenia , Ligação Proteica , Domínios Proteicos , Proteólise , Receptores Virais/química , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Relação Estrutura-Atividade , Tropismo Viral , Internalização do Vírus
17.
Soft Matter ; 17(1): 120-125, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33155013

RESUMO

How does the impact of a deformable droplet on a granular bed differ from that caused by a solid impactor of similar size and density? Here, we experimentally study this question and focus on the effect of intruder deformability on the crater shape. For comparable impact energies, we show that the crater diameter is larger for droplets than for solid intruders but that the impact of the latter results in deeper craters. Interestingly, for initially dense beds of packing fractions larger than 0.58, we find that the resultant excavated crater volume is independent of the intruder deformability, suggesting an impactor-independent dissipation mechanism within the sand for these dense beds.

18.
Liver Int ; 40(1): 83-91, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31498528

RESUMO

BACKGROUND: Tenofovir disoproxil fumarate (TDF) imposes a high genetic barrier to drug resistance and potently inhibits replication of multidrug-resistant hepatitis B virus. Few clinical cases with confirmed TDF-resistance have been reported to date. METHODS AND RESULTS: Here, we report viral rebound in a patient with chronic hepatitis B who underwent TDF monotherapy and harboured a quadruple mutant consisting of classic entecavir (ETV)-resistance mutations (rtL180M/T184L/M204V) together with an rtA200V mutation in the reverse transcriptase gene. Sequencing analysis revealed that this quadruple mutant emerged as a major viral population. In vitro phenotyping demonstrated that the rtL180M/T184L/A200V/M204V mutant had moderate resistance to TDF treatment, with a 4.52-fold higher half maximal effective concentration than that of wild-type virus. Importantly, this patient with TDF resistance achieved virological suppression after TDF/ETV combination rescue therapy. CONCLUSION: An rtL180M/T184L/A200V/M204V mutant with moderate resistance to TDF monotherapy was selected during sequential nucleoside analogue (NA) treatment in a stepwise manner. ETV/TDF combination therapy effectively suppressed replication of this TDF-resistant mutant. Our studies provide novel insights into the treatment of NA-naïve patients as well as patients with TDF resistance.


Assuntos
Farmacorresistência Viral , Guanina/análogos & derivados , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , DNA Polimerase Dirigida por RNA/genética , Tenofovir/uso terapêutico , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Genótipo , Guanina/uso terapêutico , Humanos , Pessoa de Meia-Idade , Mutação , Proteínas Virais/genética
19.
J Surg Res ; 247: 211-219, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31706539

RESUMO

BACKGROUND: The eighth edition of the American Cancer Joint Committee on Cancer (AJCC) staging system for breast cancer put forward the prognostic stage groups for the first time based on the traditional anatomic tumor-node-metastasis staging system. Our study intends to validate the predictive significance of the eighth edition staging system in triple-negative breast cancer (TNBC) patients. MATERIALS AND METHODS: We collected and accessed 26,589 eligible cases of TNBC from the Surveillance, Epidemiology, and End Results database (2010-2015) and reclassified the patient cohort according to the eighth edition of the AJCC staging system into anatomic and prognostic stages. RESULTS: The results showed that more than half of the patients upstaged in the prognostic stage when compared with the anatomic stage. By comparing with the anatomic stage, the prognostic stage had a higher likelihood ratio and linear trend χ2 values. The prognostic stage group also had higher Akaike information criterion and Bayesian information criterion values than the anatomic stage group. CONCLUSIONS: The prognostic staging system in TNBC patients performs more optimistic prognostic stratification and predictability than the anatomic staging system. Moreover, the latest AJCC staging system has a milestone importance to the history of breast cancer staging system.


Assuntos
Biomarcadores Tumorais/análise , Mama/patologia , Metástase Linfática/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Receptor ErbB-2/análise , Receptor ErbB-2/genética , Receptores de Estrogênio/análise , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/análise , Receptores de Progesterona/metabolismo , Programa de SEER/estatística & dados numéricos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Estados Unidos , Adulto Jovem
20.
Clin Immunol ; 198: 89-99, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30502542

RESUMO

BACKGROUND: Programmed cell death-1 (PD-1) and programmed death-ligand 1 (PD-L1)-targeted therapies have enhanced T-cell response and demonstrated efficacy in the treatment of multiple cancers. However, the role and clinical significance of PD-L1 expression on CD19+ B-cells and their subsets, with particular reference to systemic lupus erythematosus (SLE), have not yet been studied in detail. OBJECTIVE: The present study aimed to investigate PD-L1 expression on CD19+ B-cells and their subsets, in addition to exploring its possible role in Tfh-cell activation and B-cell differentiation in SLE. METHODS: Frequencies of CD19+ B-cells, their subsets, PD-L1 and Tfh cells in the peripheral blood of SLE patients and healthy controls (HCs) were determined using cytometry. The clinical data of SLE patients were recorded in detail, and the correlation between their laboratory parameters, clinical parameters and disease activity indices was statistically analyzed. CD19+PD-L1+B-cells and CD19+PD-L1- B-cells were sorted and cultured with a stimulant, following which the supernatants were collected for immunoglobulin G and anti-double stranded DNA detection via enzyme-linked immunosorbent assay. RESULTS: In SLE patients, CD19+B-cells and partial subgroups were enriched in peripheral blood. Also, the observed increase in the frequency of CD19+PD-L1+B-cells was significantly associated with a higher disease activity index. An in vitro culture test demonstrated that the amounts of anti-dsDNA and immunoglobulin G secreted by the CD19+PD-L1+B-cells of SLE patients and HCs were vastly different. In addition, a strong correlation existed between the frequencies of CD19+PD-L1+B-cells and defined Tfh cells of SLE patients. CONCLUSION: This study demonstrated that the expression of CD19+PD-L1+B-cells in the peripheral blood of SLE patients was abnormal, and that disease-related laboratory parameters and clinical indicators were correlated. CD19+PD-L1+B-cells were enriched and played a critical role in activating the pathogenic T-cell and B-cell responses in patients with SLE.


Assuntos
Antígenos CD19/análise , Linfócitos B/imunologia , Antígeno B7-H1/fisiologia , Lúpus Eritematoso Sistêmico/imunologia , Adulto , DNA/imunologia , Feminino , Humanos , Imunoglobulina G/biossíntese , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/imunologia
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa